Polyurethane adhesive compositions

Abstract

Disclosed are polyurethane adhesive compositions which include (a) one or more urethane prepolymers having isocyanate moieties; (b) a catalytic amount of one or more catalysts; (c) one or more forms of carbon black; (d) one or more calcium carbonates; and (e) one or more silane adhesion promoters.

What is claimed is: 
     
         1 . A polyurethane adhesive composition comprising:
 (a) one or more urethane prepolymers having isocyanate moieties;   (b) a catalytic amount of one or more catalysts;   (c) one or more forms of carbon black;   (d) one or more calcium carbonates; and   (e) one or more silane adhesion promoters.   
     
     
         2 . The polyurethane adhesive composition according to  claim 1 , wherein the one or more urethane prepolymers are derived from a polyol containing alkylene oxide units of ethylene oxide, propylene oxide or mixtures thereof. 
     
     
         3 . The polyurethane adhesive composition according to  claim 1 , wherein the one or more urethane prepolymers are derived from an aromatic isocyanate. 
     
     
         4 . The polyurethane adhesive composition according to  claim 3 , wherein the one or more urethane prepolymers are derived from methylene diphenyl diisocyanate. 
     
     
         5 . The polyurethane adhesive composition according to  claim 1 , wherein the one or more catalysts comprise one or more compounds containing one or more tertiary amine groups. 
     
     
         6 . The polyurethane adhesive composition according to  claim 5 , wherein the one or more compounds containing one or more tertiary amine groups comprise one or more dimorpholino dialkyl ethers wherein the morpholino groups may be substituted with groups which do not interfere in the catalytic effect of the one or more compounds containing one or more tertiary amine groups. 
     
     
         7 . The polyurethane adhesive composition according to  claim 1 , wherein the one or more catalysts comprise dimorpholino diethylether. 
     
     
         8 . The polyurethane adhesive composition according to  claim 1 , wherein the polyurethane adhesive composition does not contain clay. 
     
     
         9 . The polyurethane adhesive composition according to  claim 1 , wherein the one or more silane adhesion promoters comprise one or more alkoxysilane adhesion promoters. 
     
     
         10 . The polyurethane adhesive composition according to  claim 9 , wherein the one or more alkoxysilane adhesion promoters comprise one or more mercaptosilanes, aminosilanes, isocyanato silanes, epoxy silanes, acrylic silanes and vinyl silanes. 
     
     
         11 . The polyurethane adhesive composition according to  claim 1 , wherein the one or more silane adhesion promoters comprise one or more mercapto alkoxysilanes. 
     
     
         12 . The polyurethane adhesive composition according to  claim 1 , wherein the calcium carbonate is a white pigment. 
     
     
         13 . The polyurethane adhesive composition according to  claim 12 , wherein the calcium carbonate is the only white pigment. 
     
     
         14 . The polyurethane adhesive composition according to  claim 1 , comprising:
 (a) 30 to 65 wt. %, based on the weight of the polyurethane adhesive composition, of the one or more urethane prepolymers having isocyanate moieties;   (b) 0.3 to 3.5 wt. %, based on the weight of the polyurethane adhesive composition, of the one or more catalysts;   (c) 15 to 23 wt. %, based on the weight of the polyurethane adhesive composition, of the one or more forms of carbon black;   (d) 8 to 20 wt. %, based on the weight of the polyurethane adhesive composition, of the one or more calcium carbonates; and   (e) 0.7 to 3 wt. %, based on the weight of the polyurethane adhesive composition, of the one or more silane adhesion promoters.   
     
     
         15 . A method comprising
 (a) applying a polyurethane adhesive composition to at least a portion of a first substrate, wherein the polyurethane adhesive composition comprises:
 (i) one or more urethane prepolymers having isocyanate moieties; 
 (ii) a catalytic amount of one or more catalysts; 
 (iii) one or more forms of carbon black; 
 (iv) one or more calcium carbonates; and 
 (v) one or more silane adhesion promoters, 
   (b) contacting a second substrate with the first substrate; and   (c) curing the two-component polyurethane adhesive composition to form an adhesive bond between the first substrate and the second substrate.   
     
     
         16 . The method according to  claim 15 , wherein the polyurethane adhesive composition comprises:
 (i) 30 to 65 wt. %, based on the weight of the polyurethane adhesive composition, of the one or more urethane prepolymers having isocyanate moieties;   (ii) 0.3 to 3.5 wt. %, based on the weight of the polyurethane adhesive composition, of the one or more catalysts;   (iii) 15 to 23 wt. %, based on the weight of the polyurethane adhesive composition, of the one or more forms of carbon black;   (iv) 8 to 20 wt. %, based on the weight of the polyurethane adhesive composition, of the one or more calcium carbonates; and   (v) 0.7 to 3 wt. %, based on the weight of the polyurethane adhesive composition, of the one or more silane adhesion promoters.   
     
     
         17 . The method according to  claim 15 , wherein the polyurethane adhesive composition does not contain clay. 
     
     
         18 . The method according to  claim 15 , wherein the one or more silane adhesion promoters comprise one or more mercapto alkoxysilanes. 
     
     
         19 . The method according to  claim 15 , wherein the first substrate is glass or coated plastic. 
     
     
         20 . The method according to  claim 15 , wherein the first substrate is glass or coated plastic and the second substrate is an automobile, wherein the glass or the coated plastic is adapted for use as a window.